Fix up some Notices in admin

Description

Attached patch silences a lot of errors with the adition of isset()'s and use of temporary variables.

A special note needs to be given to wp-includes/taxonomy.php, A 'return null' was replaced with a WP_Error return value, The function allready returns a WP_Error on the next line for a different error condition, so it shouldnt break any code, But it may need to be replaced with a null again.

Change History (71)

Also, wp-admin/edit.php has some dead code in it, Which i commented out, I'm not sure if that needs to be kept and fixed up, or discarded all together. (See first chunk in the Diff)

Also, wp-includes/capabilities.php change added first and last names only as they can be commonly empty, I'm not sure if any other members which are added should also be prefilled to empty, However, Someone may want to take a closer look at that edit to see if it needs more default properties for the other fields.

There are too many open tickets for PHP notices, but thanks. It was getting annoying seeing all of the notices. I think also the problem is that some notices only appear when the cron runs or you do an action.

I'm going to check your current patch to see if you fix these issues. I think that eventually, the notices will be found again, but it is nice to have a record of all the current patches of where notices have been found by people. Which is why I kept the #6669 ticket. There are currently only two tickets (that I know of) that exist on this issue.

#6669 isn't completed, but if you want to close that to keep this one open, then that might make more sense. However, it will be a good idea to go over the duplicated tickets referenced in #6669 to make sure something wasn't forgotten.

Can the last two patches go in? Probably won't fix the ticket until the administration panel changes stop and the notices can be checked again, however, it would be nice to have these two patches in to ensure that new notices are corrected instead of releasing patches that already fixed the notices.

The dashboard basically assumes theres posts posted, In the case where there are no posts, things break, That fix in the patch isnt the best, Its mainly as a reminder to whoever finishes all the TODO's (The other code branches probably suffer the same thing)